while循环正在为变量赋值，我稍后将使用它，但不确定

Question

read -p "Enter the new Kernel Destination: " kernel_new
n=1

while [ "$word" != "no" ]
do
read -p "Enter the Hostname: " hostname_$n
read -p "Enter the SID: " sid_$n
read -p "Enter the destination of Kernel: " kernel_old_$n
read -p "Want to add new entry please give yes or else give no: " word
n=$(( n+1 ))
done

echo "Kernel Upgrade is starting now"

while [ $n != 0 ]
do
echo "Upgrading ${hostname_[$n]} "
n=$(( n-1 ))
done

执行：

我想要显示"Upgrading hostname“，在用户提示期间，将在我的第一个while循环中分配hostname。假设hostname_1 =abcdef，hostname_2=qwerty

然后我希望输出结果为

Upgrading abcdef
Upgrading qwerty

请救命！

壳

while [ $n != 0 ]
do
echo "Upgrading ${hostname_[$n]} "
n=$(( n-1 ))
done

我想要显示"Upgrading hostname“，在用户提示期间，将在我的第一个while循环中分配hostname。所以假设

hostname_1 =abcdef, hostname_2=qwerty

然后我希望输出结果为

Upgrading abcdef
Upgrading qwerty

请救命！

Answer 1

这些变量在子while中的while循环中捕获，在外部不可用。但是您可以尝试使用关联数组。下面是一个简单的例子，说明它是如何工作的：

#!/bin/bash

# declare an associative array
declare -A dict
n=0
while true; do
    read -r -p "Hostname: " dict['hostname_'$n]
    read -r -p "retry? (Yn): " answer
    [[ "$answer" == "n" ]] && break
    (( n++ ))
done 

# loop over all entries in reverse order
for i in $(seq $n -1 0); do
    printf "%s\n" "${dict['hostname_'$i]}"
done